Furnace construction



March-1 8, 1930. 5w, BENNIS 1,751,188

FURNACE CONSTRUCTION Filed NOV. 2, 1923'," 9 Sheets-Sheet 1 March 18, 1930. A. w. BENNIS FURNACE CONSTRUCTION 4 9 Sheets-Sheet 2 Filed NOV. 2, 1925 March 18, 1930. A. w. BENNIS 1,751,138

FURNACE CONSTRUCTION Filed Nov. 2. 1925 9 Sheets-Sheet 3 Fig.5. 48

March 18, 1930. A. w. BENNIS FURNACE CONSTRUCTION Filed Nov. 2,. 1925 9 Sheets-Sheet 4 March 18, 1930. A. w. BENNIS 1,751,188

FURNACE CONSTRUCTION Filed Nov. 2, 1925 9 Sheets-Sheet 5 M'amh 18, 1930. A. w. BENNIS 1,751,188

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' FURNACE CONSTRUCTION Filed Nov. 2, 1925 9 Sheets-Sheet 7 L55 FAQSgfi p 47 I 50 X49 5 j a? a; 47a c $4M W j /W March 18, 1930.

A. W. BENNIS FURNACE CONSTRUCTION Filed Nov. 2, 1925 9 Sheets-Sheet 8 A. W. BENNIS FURNACE CONSTRUCTION FiledNov. 2, 1925 EU W 1 m W F 1% W 1 m +w W 1 1 Wmm 7 1 Filly.

March 18, 1930.

Patented Mar. 18, 1930 PATENT orricr.

ALFRED WILL'IA'M BENNIS, F BOLTON, ENGLAND FURNACE CONSTRUCTION Application filed November 2, 1925,8eria1No. 66,423,*and in Great Britain November 10, 1924.

The present invention relates to improvements in the construction of furnaces which is particularly suitable for application to furnaces of steam generating boilers.

According to the present inventionone or more or part of the furnace walls are suspended froman outer frame work,-so that vertical expansion of .the said walls will take place .in a downward direction in contradis- 0 tinction to the upward direction only as hitherto.

Further by .the present invention one or more or part of the furnace walls are wholly or partially suspended from overhead supporting structure or framework, constructed of joists or girders of steel or other suitable material, the said structure or framework being itself supported by means ofcolumns or in'some other suitable manner.

The overhead supporting structure or framework may. serve alsoforthesupport of the metallic structure ofa boiler, or of the furnace .roof, or of any other suitable structure or equipment for which support is required. it has of course already been known to suspend a furnace arch from overhead girders. i

The invention is more particularly ,described with reference to the accompanying drawings, in which:

- Fig. 1 .is-asectional .view.on.line 1-1 of Fig. 2, behind a furnacefront of one form of suspended wall constructed according to the present. invention.

Fig. 2 isa partial .side view ofFig. ,1 showing a-method ofsuspending the brick supporting sill platefrom metal work above the furnace in attachment to the ja-mb columns of. thefurnaceifront.

.Fig. 3 is a corresponding plan view with partial section onlinel3-3 of Fig. 2.

Fig. .4 is a partial view substantially on liI1G.4-+h0f Fig. 2, showing a sidejamb col-' umn, aside jamb plate anda crown plate at the front of the furnace. I

Fig. 5 shows in side elevation, a second form of constructionfor a suspended front furnace wall in combination with a suspended flat. arch, withia parti'al sectionon line'5-5 of.Fig..6.

' Fig. 6 is a correspondingfront sectional view of Fig. 5. n

Fig. 7, is a sectional View similar to Fig. 5 through part of a further modified furnace with a suspended front wall in combination with a sprung or curvedarch.

Fig. 8 shows a further modified .form of con'structionof suspended side wall of a furnace in combination with a lower section of wall supported upon the floor.

Fig. 9 shows another form of abrick supporting sill plate in attachment with a ventilated tension member supporting the wall.

Fig. 10 is a side sectional elevation on line 10 10 of Fig. 8, of the lower brick supporting plate shown in Fig. 8 with its attachment to a ventilated'tension member.

Fig. 11 is a further modification showing a sectional elevation of a chain grate furnace to which'the invention has been applied.

Fig. 12 shows details on an enlarged scale of the furnace side wall shown in Fig. 11.

Fig. 13 is a corresponding partial sectional side view on line 1313.of Fig. 12 of the lower part of the suspended wallshown in Figs. 11 and 12.

.Fig. 1. 1 is a sectional elevation of a further modification showing a boiler in which suspended baffle walls have been applied constructed according to the present invention.

Fig. 15 is a section on line 15-15 ofFig. 141 on an enlarged scale, of the suspendedbafile walls. i

Fig. 16 shows a detail in section on line 16-46 ofFi'g. 15 of the method of construct ing the suspended boiler baflle walls shown in Figs. 14 and 15.

'Fig. 17 is a corresponding horizontal section substantially on line 1717 of Fig. 15.

Figures'l'to' l indicate by way of example, an arrangement in which the supporting metal work of a suspended flat arch may be combined with the support of suspended-furnace walls, Fig. 1 in particular indicating-anad-* vantage of such a type of construction whereby a free space may beprovided undereach furnace side wallalong the sides of amechanically operated grate, as for instance, along the sides of a chain grate stoker.

The jamb column 25, Figs. 21 to 4,.as comvantage of reducing the formation of slag or 1 monly employed at the front and sides of a mechanically operated grate, is attached to and supports girders orjoists 26, which girders or joists may be additionally supported at their rearward ends by being attached to the supporting metal work of a boiler or by other suitable supporting means. The girders or joists 26,'in addition to their function of supporting the furnace side walls 30, may be used to support lateral joists'27, such as may be required for the support of fire brick blocks 31 of a suspended fiat furnace arch. The jamb column 25 may also be used to support a jamb plate or plates 24 at the sides of the front of the furnace, in addition to the crown plate or plates front of the furnace.

The girders or joists 26 support the tubular tension members or hangers 29 carrying the brick work 30 at the sides of the furnace. This brickwork rests upon and is supported by metal sill plates 32, which maybe attached to and be supported by flanges 23 or their equivalent, aflixed to the tubular tension members or hangers 29. Similar flanges 23 may be used to attach the tension members 29 to the supporting joists or girders 26. By the employment of hollow tension members or hangers, a circulation of air maybe provided through such hangers, by which the metal of the hangers will beprevented from becoming overheated to an objectionable degree. In addition, the temperature of the interior of the furnace side walls will be maintained at a lower degree than is the case with solid brickwork as ordinarily erected, whereby the durability of the suspended side walls is materially increased, in addition to the adclinker on the fire brick at the sides of the furnace adjacent to the fire.

By the employment of furnace side walls, suspended according to this invention, a clear open space may beprovided in whole, or in part, along the outer side of a mechanically operated grate, as for instance, a chain grate 36. In the case of a chain or other grate employing forced draught, as in the case of a compartmental or cellular type of grate, the clear space so provided may be employed for the installation of suitable air inlet, damper and clean-out boxes or air ducts as at 33,

without interference with any supporting stanchions or other metal work such as is C commonly employed for the support of fur nace walls when supported upon the floor.

Furthermore, in the case of comparatively thin furnace walls, 34, situated between two grates, the support of such walls can be made more secure by the use of hollow suspension supports 29 than has heretofore been the case when such centre walls have been erected upon a thin supporting sub-wall structure, or upon narrow and insecure upright stanchions attached to the sill plates 32 at their upper 28 over the top of the ends and resting on the floor at their lower ends. In addition, the use of the hollow suspension supports 29 provides an efficient means for cooling the interior or core of the middle wall 34, by means of which cooling the life of this brickwork, which is heated on both sides, is considerably increased in comparison with centre walls between furnaces as heretofore commonly constructed.

In lieu of employing tubular tension bars or hangers as at 29, the tension members may be in the form of rods or bars 37, shown by Fig. 5, arranged with an outer ventilating protective tube or casing 38 or 38, as shown byFigs.5to7.

As shown by Fig. 5, a front suspended wall of a furnace is supported from a lateral girder or joists 26, which, in addition, is utilized according to this invention to support the rearward ends of the metal hangerbars 41, employed for the support of suspended fiat arch work 42. In this case, the forward ends of the metal hanger bars 41 may be sup ported by lateral joists 44, according to a usual manner. i

As shown in Figs. 5 and 6, the front suspended brick wall 45 is supported by resting upon the metal suspension plates 39 These plates 39 may be attached to the suspension rods 37 in the manner shown at 40, by which air can circulate into the protective covering 38 around the rod 37, by the employment of a star shaped openwork cast section or its equivalent at the point of attachment of the rod to the plate. The suspension plates 39, as particularly shown in Fig. 6, may be provided with grooves for the clamping and support of the rearward ends of the metal hanger bars 41, as employed for the support of Ithe brick blocks 42 of a flat suspended arc Figure 7 shows a type of furnace wall construction similar to that shown by Figs. 5 a

and 6, except that in this case the roof 46 over the furnace is of the arched construction in lieu of being a flatsuspended arch. In this case, the tension rod 37 is attached to a bottom flange 40, of an openwork type which may be of star shape and, in turn, is used to support the brick supporting plate or plates 39.v By this arrangement, the air can pass into the ventilating protective covering 38 around the rod 37.

Ventilating openings 84 in the brickwork,-

may be provided at the upper ends of the protective coverings 38 or 38 as shown by Figs. 5 and 7 in order to ensure a circulation of air through the protective coverings around the suspension rods 37 by which these rods cannot become overheated to any objectionable degree. v a

Figs. 8 to 10 in particular show a method of attachment of the tensionbars to the suspension brick supporting plates to allow of free flow of air through the enclosing tending grate partition.

tube, and also, if desired, through a lower hollow wall 52 supported from below and independent of the upper suspended wall 53.

In Figs. 8 and 10 a flange 54, provided with a star shaped opening around a central bolting hub, bears against the brick supporting plate 39 supported by tension bars 37, having passages 55 for the passage of cooling air from or to the tube 38 into or from the lower floor supported wall 52.

In lieu of employing a separate flange 54, the tension bars 37 may be directly attached to the brick supporting plate 39 for example, as in the manner shown by Fig. 9.

One of the features of the present invention resides in the employment of means by which a furnace or boiler wall can be supported in sections, each section resting upon its own supporting plates 39, 39 or 39 with, if desired, the lower section of the wall 52 resting upon the floor 56 as shown by Fig. 8. It will be noticed that on the furnace side of the suspended wall at each brick supporting plate 39, the exposed fire bricks 52 and 53 are formed so as to provide a slip joint on the furnace side at each brick supporting plate 39.

Referring to Fig. 11 the sill plates 32 are all employed and it will be seen that steam generating or water circulating tubes 64 passing from lower headers 57 to upper headers 56, may be associated with the walls 58 to cool these, or to protect such walls 58 and their lower removable bricks 51 from the heat of the furnace having as an additional function the increasing of the water heating and steam generating surface of the boiler. The grates 61 are located between the side walls and an intermediate upwardly ex- The vertical headers 65 to which the lower headers 57 are attached, form a means of including the tubes 64 in the boiler circulation.

Figure 12 shows in detail the construction 53 of the furnace and boiler sidewalls with the supporting plate 39 shown in the general arrangement set forth by Fig. 11. Forthe purpose of providing means whereby the lower brick blocks 51 of the side suspended walls can be renewed, these blocks are slipped on to metallic T-shaped hooks 50. These hooks are, in turn, supported by their respective box castings 47 by means of a key 49 which key, 'upon being withdrawn, permits the overlapping upper end of the T-shaped hook 50 to be lowered through the opening 48 in the lower portion of the box casting 47. By this means, the lower renewable fire brick blocks 51 can be removed from the bottom part of the suspended wall, and replaced by new blocks when necessary. If desired, the fire brick block 51 which is nearer to the centre of the furnace can be removed by being slipped from the T-shaped hook 50 without removing the. book from its supporting box casting 47. I

The suspended furnace or boiler side walls, are supported at intervals by means. of the tension bars or rods 37 which. are, in turn, suitably'attached to a. supporting structure at the top of the furnace or boiler, as, for instance, by means being'attached to the joists or girders 26, shown on Fig. 11. 1

At intervals along the suspended wall, where the wall is supported by the tension bars or rods 37, enclosed in a ventilating pipe or tube 38, the bottom of each tension rod is bolted, to its respeztive box casting 47., The. box castings 47, which are so attached to their respective tension supporting rods-v 37 in ad dition to their function of supporting the lower brick blocks 51, are employed for the purpose of supporting the brick supporting ledge plates 39. In Figs. 12 and 13 these ledge plates 39 are shown as resting upon the upper flanges of the box castings 47 at. tached to the tension rods 37.

The ledge plates 39, in addition to their function of supporting the brickwork of the suspended side walls, may also be employed for supporting intermediate box castings 47, or their equivalent, which in turn may be utilized for the support of their respective lower renewable firebrick blocks 51, by means of hooks 50, held in place by removable keys 49. When so employed the intermediate box castings 47, may be attached to their supporting ledge plates 39 by means of a bolt, or bolts 53, inserted through projecting flanges of the ledge plates, or if desirable, any other suit able method can be employed for connecting the ledge plates to the intermediate box castings 47 At the sides of the furnace, situated below and wholly or partially exterior to. the bottom sections of the suspended walls, additional furnace walls may be employed, as shown at 52 on Figs. 11 and 12. These walls may, if desired, be supported upon the floor or foundation work of the boiler or furnace, in which case the lower walls 52 will expand upwards, due to heat, while'the suspended walls 58 will expand downwards. For thisreason a sliding joint is required at the faces of contact between the lower floor supported walls 52, and the lower section ofthe upper suspended wall 58. Along the lines of this sliding oint, and in order to make this joint substantially air-tight, asbestos or other suitable packing may be employed.

In order that the floor supported wall 52 may be maintained in proper contact and relationship to the upper suspended Wall 58, the outer surfaces of such walls may be pros vided with an exterior metallic framework,

or otherwise suitably attached,

shown in part at the points 55 on Fig. 12, in

order to provide for the expansion and contraction of the suspended walls, the attaqch v ments between the metal work of the sus-' pended walls and the metal work of the exterior framework 55, may be made by means of sliding connections as shown by way of example at the point 56on Fig. 12.

' An important advantage of constructing ''-furnace and boiler side walls accordin to nace or boiler.

this invention, as illustrated by way of exampleby Figs. 11 and 12, is that it is possible to install one or more mechanically operated or hand-fired grates 61- having an overall width greater than the distance be tween the boiler walls 58 at the sides of the boiler.

'An important advantage of employing a floor supported wall at the sides of a grate in combination with an uppersuspended wall at the sides of a furnace or boiler, as shown by Figs. 11 and 12, is that repairs can easily be made to the lower floor supported wall, without in any way disturbing the structure of the upper suspended side wallof the fur- Such repair work to the brickwork at the sides of a furnace is generally difficult, when the entire wall construc tion at the sides of the furnace or boiler is erected'upon the floor or other foundation work.

\In another form of the present invention, the walls enclosing a furnace, equipped for the combustion of powdered, liquid or gaseous fuel, may be suspended in whole or part from an overhead metallic or othenstructure, as, by way of example, the upper ventilated side walls 81 shown on Fig. 14 of the furnace provided with combustion noz zles or burners 80. According to Fig. 14 the suspended walls 81 are shown as being supported by means of supporting tension rods, bars, or pipes attached at their upper ends to the joists or girders 83.

In addition the suspended walls 81 are shown as being employed in combination with a fiat suspended arch construction 82 over the top of the combustion chamber. 7 In this case, the metal work used for the support of the suspended fiat arch 82 is employed in structural combination with the metal work used for the support of the side suspended walls 81. V I I The methods employed for the construction of suspended furnace or boiler walls may also be employed in whole, or part for the construction of the ventilation suspended boiler baffle walls 75, as shown in Fig. 14, which walls are shown as being suspended from the upper framework of the furnace and boiler such for instance as the cross girders or joists 76, which are attached to and support the tubular tension supports 66. 7 These supports may form air passages, leading air from the air trunks 79. The tubular tension supports 66 may be discharged into the interior of the furnace through the outlet ports 78, for the supply of air for the'combustion of the fuel.

The suspended. baffle wall construction shown in Fig. 14 is illustrated ingreater detail in Figs. 15, 16 and 17. Tubular tension supports 66 are supported from the over head structure and directly carry the brickwork 67 upon flanges or plates 68. These plates support similar flanges or plates 69 of the next tier of brickworkbelow, bybolts 70, to allow partially hollow intermediate bricks 71 to serve as air outlet ports from the tubular tensionsupports 66. The lowermost set of flanges or plates 68 carry rails 72 the flanges of which form keys to support the suspended brick blocks 73 and 74, all formed in a manner by which these suspended blocks are made easily renewable when desired. The upper row of suspended blocks 73 may be partially hollow to'serve as additional air outlet ports along the bottom portion ofthe suspended baffle wall. I 4

Ideclare that what I claim is I v 1. A boiler furnace comprising an overhead frame work, tension bars depending from said frame work, walls solely supported upon said tension bars, protective tubes around said tension bars, and means whereby air may be passed through the space .between said tubes and said bars.

2. A boiler furnace comprising an overhead framework, a vertical wall, a wall support at the bottom thereof, itie members acting in tension and extending between the framework and support to carry'the wall, and means whereby air may be passed along the length of said tie members to cool the 100 same. I V V 3. Aboiler furnace comprising an overhead framework, a vertical wall, vertical air ducts in said wall, a wall support at the bottom of said wall, tie members acting in ten- 105 sion and extending through said ducts from the framework to the support to carry the wall and ducts, and means-whereby air may be passed. through the ducts to-cool the ducts and tie members. y

4. A boiler furnace comprising an overhead framework, vertical walls, a wall support intermediate the height of the wall to carry the part of the wall thereabove, tie

members acting in tension and extending be ALFRED WILLIAM BEN NIS. 

